You might want to check (call) Bacon & Associate's consignment in Annapolis.

They are better known as "Bacon Sails", but consign everything nautical. (even power boat stuff........eeewwww)

I wandered into their "back room" and they had at least one mast worthy of scrutiny as a replacement for the Ariel: one for a Bristol 27. It didn't have the mast lengtH on the tag, but the I,J,P,E measurements are within a foot or so, depending on exactly which Bristol it was for.

You might want to call them directly on Monday and inquire about it.

What caught my eye was that it had the exact same spreaders and spreader bases (the castings) as the Ariel. Curiously, it didn't have a bolted/screwed-on external mainsail track; it had an internal track for slugs.
The teardrop shape of the mast looked the same to my eye as the original Ariel extrusion, but where the teardrop narrows to a flat spot on our masts, this had an extension on the back. It wasn't bolted on, or added later; it looked like a slightly different extrusion, but only in the sail track area.

They also had a boom if I remember correctly.

But they had at least a dozen other masts and two or three dozen booms to choose from.

Bacon's info is:
Bacon & Associates, Inc.
116 Legion Ave.
Annapolis, MD 21401
410-263-4880
shop hours:
mon-fri 10am-5:30pm EST

(Saturday's are optional for them, but mostly they are open 8am-12pm on sat)

Good Luck!